Capacitors may have many uses in integrated circuitry. For instance, capacitors may be incorporated into memory circuitry (e.g., dynamic random access memory (DRAM)), control circuitry, sensors, etc. Integrated capacitors generally have a storage node electrode, a dielectric material, and a plate electrode; with the dielectric material being between the storage node electrode and the plate electrode.
Two general types of capacitors are crown-type capacitors and stud-type (also referred to as pillar-type) capacitors. Crown-type capacitors have the storage node electrode configured in a container-shape, and may have the dielectric material and plate electrode extending into the container-shaped storage node. In contrast, stud-type capacitors have the storage node electrode configured as a pillar, and have the dielectric material and plate electrode extending around the pillar.
A continuing goal of integrated circuit fabrication is to increase integration density. A related goal is to develop capacitor architectures which consume a relatively small footprint over a semiconductor base, while still achieving suitable capacitive storage. Accordingly, capacitors may be formed to be increasingly tall and thin with increasing levels of integration.
As capacitors become increasingly tall and thin, the capacitors are subject to toppling. Stud-type capacitors may have increased structural stability as compared to crown-type capacitors, and accordingly may be more resistant to toppling than crown-type capacitors. However, difficulties have been encountered in obtaining consistent and uniform performance across arrays of highly integrated stud-type capacitors. It is desired to develop improved stud-type capacitor architectures.